Number bonds: the family of a number

Grades K–2

The big idea

Every number can be split into two parts that go back together.

Think of it like a number is a family that can sit in two rooms: Five can sit as 1 and 4, or 2 and 3: same family, just split across two rooms.

Split the family

Take 5 blocks. Put some in your left hand, some in your right. 1 and 4? 2 and 3? However you split them, it's still the same 5 when you bring your hands together.

and

first group2

next group3

2 and 3 together is 5.

Wonder out loud

These are good questions to ask: yourself, a grown-up, or your math helper.

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